High Precision Spindle Ball Bearings
GRW: highest speed and great bearing capacity
GRW spindle ball bearings are suitable for applications, such as machine tools, requiring precision while carrying a high load capacity combined with high speed.
Spindle ball bearings are single-row angular contact ball bearings (separable ball bearings) with a nominal contact angle of 15° or 25°. They can be subjected to both radial and (in one direction) axial loads. The direction of the axial load carrying capacity is shown by a marking on the outer ring.
GRW spindle ball bearings are characterised by the following properties:
- Manufacture in grade P4 (or ABEC7) or better
- Rings generally made of corrosion-resistant SV30 high-grade steel
- Steel or ceramic balls available for all types
- Machined solid retainer of fiber-reinforced phenolic resin or special materials, for example for applications involving higher temperatures
15° (C) or 25° (E) contact angle as a standard
- Optionally, bearings can be paired with three pre-defined preload classes (L, M, S) or individual preload
- Oil or grease lubrication
- Open and closed versions available
- Assembly, lubrication and packaging pursuant to cleanroom grade 10,000
Open spindle ball bearings
- Standard version with large balls for optimum utilization of the bearing interior and solid retainer for high bearing capacity.
- The outer ring has one shoulder only. The increased height of the snap feature prevents bearing collapse.
- Solid retainer guided on outer ring with low cross-section, particularly well suited for oil injection lubrication.
Closed spindle ball bearings
- The non-contact shields do not cause any additional friction torque
- The standard shields made of Viton with metal stiffener offer excellent temperature and media resistance
- Very narrow sealing gap for high dust protection
- Recommended for grease lubrication, increases the longer service life
- Same outer dimensions as open spindle bearings
- This design requires often smaller balls, resulting in a lower bearing capacity but higher axial stiffness and speed limit (usually signified by an index letter after the basic type in the part number).
- Also available without closure as high-speed version
- Leave the bearing in its air-tight package until you are ready to start the assembly.
- Ensure extreme cleanliness at the workplace.
- Avoid shocks and impacts.
- Axial load must only act on spindle bearings as indicated by the <s></s>marks on the outer ring.
- Use suitable assembly tools to ensure that no assembly forces can be transferred through the balls.
- Duplex bearings of pairing types -1 (DB), -2 (DF), -3 (DT) are always packed in pairs and can only be assembled in the specified arrangement with the other bearing in the package.
- Universally matched bearings can be freely paired with each other, i.e. you may combine bearings from different packages or lots. These bearings may be assembled in any arrangement.
- Before start of operation, allow the bearing to run in at high speed.